Occupancy-based demand controlled ventilation system

• US 9,528,715 B2
• Filed: 12/02/2009
• Issued: 12/27/2016
• Est. Priority Date: 12/02/2009
• Status: Active Grant

• Current Assignee: Thomas David Aiken
• Original Assignee: Thomas David Aiken
• Inventors: Aiken, Thomas David
• Primary Examiner(s): TOMPKINS, ALISSA JILL
• Assistant Examiner(s): Towns, Brittany
• Application Number:
  US12/591,803
• Publication Number:
  US 20110127340A1
• Time in Patent Office: 2,582 Days
• Field of Search: 454/254, 454/256, 454/258, 700/276
• US Class Current: 1/1
• CPC Class Codes: F24F 11/0001 for ventilation F24F11/30 takes precedence
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 11/74 for controlling air flow rate or air velocity
• CPC Class Codes: F24F 2120/10 Occupancy
• CPC Class Codes: G05B 15/02 electric

Abstract

In a demand control ventilation (DCV) system, ID codes of tags worn by occupants are detected in each room by a tag detector and wirelessly communicated to a zonal occupancy compiler. The zonal occupancy count arrived at by the compiler is transmitted to a DCV microprocessor, which interfaces with the ventilation controller of the building'"'"'s HVAC system and sets the zonal ventilation rate based on the occupancy count and applicable ASHRAE standards.

Claims

1. A system for adjusting a ventilation rate of each of a plurality of ventilation zones within a building occupied by a plurality of occupants, the system comprising:

(a) a plurality of tags, each tag of the plurality of tags having a digital ID code that is assigned to a corresponding occupant of the plurality of occupants, wherein a ventilation zone of the plurality of ventilation zones includes a first room and a second room;

(b) a first one or more tag detectors for detecting a first subset of tags of the plurality of tags located in the first room during a time interval, and a second one or more tag detectors for detecting a second subset of tags of the plurality of tags located in the second room during the time interval;

(c) a plurality of zonal compilers assigned to the plurality of ventilation zones and including a zonal compiler assigned to the ventilation zone, the zonal compiler configured to;

communicate wirelessly with the first one or more tag detectors and the second one or more tag detectors, and/or with the first subset of tags and the second subset of tags to thereby wirelessly acquire a first group of digital ID codes corresponding to the first subset of tags detected by the first one or more tag detectors during the time interval, and a second group of digital ID codes corresponding to the second subset of tags detected by the second one or more tag detectors during the time interval;

compare the first group of digital ID codes with the second group of digital ID codes;

based on said comparison, identify a tag of the first subset of tags as being the same as a tag of the second subset of tags,

eliminate the identified tag from the second group of digital ID codes to establish a corrected second group of digital ID codes, and

compute a zonal occupancy count for the zone based on the acquired first group of digital ID codes and the corrected second group of digital ID codes;

(d) one or more DCV processors for wirelessly interfacing with the plurality of zonal compilers, wherein at least one of the one or more DCV processors is configured to receive the zonal occupancy count from the zonal compiler and compute a zonal ventilation rate based on the received zonal occupancy count and a floor area of the ventilation zone; and

(e) one or more HVAC interfaces for wirelessly interfacing with the one or more DCV processors, wherein the one or more HVAC interfaces adjusts the ventilation rate for the ventilation zone to conform to the zonal ventilation rate computed by the one or more DCV processors.

2. The system according to claim 1, wherein a first controlled space code is assigned to the first room and a second controlled space code is assigned to the second room, and wherein the first controlled space code is wirelessly communicated by the first one or more tag detectors to each tag of the first subset of tags located in the first room, and wherein each tag of the first subset of tags wirelessly communicates the first controlled space code, along with the tag'"'"'s digital ID code, to the zonal compiler.

3. The system according to claim 1, wherein one or more of the plurality of zonal compilers incorporates a DCV processor.

4. The system according to claim 2, wherein one or more of the plurality of zonal compilers incorporates a DCV processor.

5. A process for adjusting a ventilation rate of each of a plurality of ventilation zones, each ventilation zone having a determined floor area, within a building occupied by a plurality of occupants, the process comprising the following steps:

(a) assigning a tag of a plurality of tags to each occupant of the plurality of occupants, each tag of the plurality of tags having a digital ID code;

(b) providing in the ventilation zone a first one or more tag detectors and a second one or more tag detectors;

(c) initiating wireless communications during a time interval between the first one or more tag detectors and a first subset of tags of the plurality of tags located in the first room, and between the second one or more tag detectors and a second subset of tags of the plurality of tags located in the second room;

(d) providing a plurality of zonal compilers assigned to the plurality of ventilation zones and including a zonal compiler assigned to the ventilation zone;

(e) initiating the zonal compiler to;

wirelessly communicate with first one or more tag detectors and the second one or more tag detectors, and/or with the first subset of taps and the second subset of tags to thereby acquire a first group of digital ID codes corresponding to the first subset of tags detected by the first one or more tag detectors during the time interval, and a second group of digital ID codes corresponding to the second subset of tags detected by the second one or more tag detectors during the time interval,

compare the first group of digital ID codes with the second group of digital ID codes,

based on said comparison, identify a tag of the first subset of taps as being the same as a tag of the second subset of tags, wherein the identified tag moved between the first room and the second room during the time interval,

eliminate the identified tag from the second group of digital ID codes to establish a corrected second group of digital ID codes, and

compute a zonal occupancy count for the zone based on the acquired first group of digital ID codes and the corrected second group of digital ID codes;

(f) providing one or more DCV processors;

(g) initiating communications between the one or more DCV processors and the plurality of zonal compilers, whereby at least one of the one or more DCV processors is configured to receive the zonal occupancy count from the zonal compiler and compute a zonal ventilation rate based on the received zonal occupancy count and a floor area of the ventilation zone;

(h) providing one or more HVAC interfaces; and

(i) interfacing the one or more HVAC interfaces with the one or more DCV processors, such that the one or more HVAC interfaces adjust the ventilation rate for the ventilation zone to conform to the zonal ventilation rate computed by the one or more DCV processors.

6. The process according to claim 5, comprising the further steps of assigning a first controlled space code to the first room and a second controlled space code to the second room, and wirelessly communicating the first controlled space code by the first one or more tag detectors to each tag of the first subset of tags located in the first room, and wirelessly communicating the first controlled space code by each tag of the first subset of tags, along with the tag'"'"'s digital ID code, to the zonal compiler.

7. The process according to claim 5, wherein one or more of the plurality of zonal compilers incorporates a DCV processor.

8. The process according to claim 6, wherein one or more of the plurality of zonal compilers incorporates a DCV processor.